POLICE in Crewe are urging people to be vigilant after powerful detonators packing enough gunpowder to cause serious injury were stolen from a van.

They say the effects could be disastrous if the devices end up in the hands of children or anyone coming across them unwittingly.

The small, circular detonators are used by the rail industry as safety devices to warn oncoming trains about incidents on tracks such as breakdowns or electrical faults.

They are fastened to the rail by two attached lead straps and omit a loud bang to alert train drivers of problems.

The explosives were stolen between 9 and 9.30pm on Wednesday when the thief broke into a red Transit van parked on the junction of Rigg Street and Eardley Court in Crewe.

The thief rummaged through a box containing eight of the bright yellow devices and took four of them before fleeing the scene.

Police believe the culprit has sustained an injury to his or her hand when smashing the van's window. They found blood stains on a first aid box in the vehicle.

Both the box and the van, which is owned by a rail engineer, are being examined by forensic experts in a bid to trace the suspect.

Inspector Julia Westgate, of Crewe Police, said: 'We have no idea why anyone would want to steal these detonators.

'They are extremely dangerous in the wrong hands. The consequences could be disastrous if children were to get hold of them as they might see them as toys.

'We're treating this situation very seriously and urge anyone with any information about the theft or the whereabouts of the detonators to call us immediately.'

Crewe British Transport Police officer, PC David Lowe said: 'The detonators are only about three inches in circumference and between five to 10mm in thickness. But they could take someone's hand off if they explode.

'The noise it makes is ear-shattering.'

Anyone with information is asked to phone Crewe Police on 01244 350000 or Crimestoppers on 0800 555111.